The Experiment of Permeable Ceramic as Sound Absorption Material

Badaling Station, one of the stations along Beijing-Zhangjiakou High Speed Railway, is the deepest high speed rail station in China with a depth of 102m.Ceramic was never considered as a sound absorption material. But for this underground HSR station, the sound absorption material should be fireproof, water not soluble, durable, artistic and with Chinese characteristics. Ceramic is perfect only if it is sound absorptive. Permeable ceramic is a new material developed by a ceramic expert in China. 24 samples of permeable ceramic in different clay or glaze were tested to find out their flow resistance. And the 2 samples with the highest and lowest flow resistance wear tested to get their sound absorption coefficient by stand wave tube. The test result shows that the permeable ceramic has an average sound absorption coefficient (100Hz~2000Hz 1/3 octave band) from 0.13~0.20. This article will detailed introduce the whole process of the acoustical test, and analyze the 24 permeable ceramic sample by micro graph.